HXK6 actin

Fig. 6 The expression patterns of hexokinase related genes in TNG67 and transgenic plants after inoculation with Xoo (10⁹ cfu ml^-1). RNA was isolated from 1 month old seeding of TNG67 and two transgenic plants under 0 hr, 8 hr, 24 hr and 48 hr Xoo treatment for a RT-PCR and b qRT- PCR analysis to detect HXK1 (hexokinase 1), HXK2 (hexokinase 2), HXK5 (hexokinase 5), HXK6 (hexokinase 6) gene expression patterns and the expression of actin as internal control respectively.

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(A)

Fig. 7 Comparisons of DAB stain and H2O2 content between TNG67 and transgenic plants after inoculation with Xoo (10⁹ cfu ml^-1). a Localization of ROS in leaf tissues by using DAB stain assay after treatment for 0 hr, 8 hr, 24 hr and 48 hr. DAB (1mg/ml) polymer by reddish-brown coloration indicates the presence of ROS. Scale bars are 1 cm. b Detection of H2O2 content in leaf tissues of TNG67 and transgenic plants that grown for 1 month after inoculation Xoo for 0 hr, 8 hr, 24 hr and 48 hr. The values of solid bar for two pflp transgenic plants were significantly different from TNG67 according to one-way ANOVA LSD Means Test (P < 0.05). The results are given as means ± SD (n=3 individual plants).

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(A)

Fig. 8 The expression patterns of pathogenesis-related genes in TNG67 and transgenic plants after inoculation with Xoo (10⁹ cfu ml^-1). RNA was isolated from one month old seeding of TNG67 and two transgenic plants under 0 hr, 8 hr, 24 hr and 48 hr Xoo treatment for a RT-PCR and b qRT- PCR analysis to detect gene expression patterns of PR1a (Pathogenesis-related protein 1a), PR1b (Pathogenesis-related protein 1b), TLP (thaumatin-like protein), Sci1 (subitilisin-chymotrypsin inhibitor), PBZ1

(probenazole-inducible protein), PAL (phenylalanine ammonia lyase) and actin as internal control respectively.

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Fig. 9 Proposed model for the role of PFLP in sugar signal-regulation during defense response in transgenic plants. (1) PFLP increases photosynthesis efficiency and glucose production in normal growth. (2) PFLP enhances ROS generation during pathogen infection. (3) Sugar pools act as a sucrose source during pathogen infection. (4) cwINV1 catalyzes the hydrolysis of sucrose into glucose and fructose in apoplast. (5) CT-BMY catalyzes the breakdown of starch into glucose in chloroplast. (6) HXK2 and HXK6 expressions were enhanced by glucose accumulation in plant cell in the process of pathogen infection. (7) Glucose accumulation leads to increase of pyruvate content, which affects the TCA cycle, one of the ROS generation site in plant. (8) NIN1 catalyzes the hydrolysis of sucrose into glucose and fructose in mitochondria. (9) HXK6 is linked to mitochondrial ROS production. (10) ROS is as a signaling active antioxidant system and PR gene expression. sucrose (S); glucose (G); fructose (F); glucose 6-phosphate (G6p);

pyruvate (Pyr); photosynthetic electron transport chain (PETC); tricarboxylic acid cycle (TCA); reactive oxygen species (ROS); invertase (INV); hexokinase (HXK); β-amylase (BMY); hexose transporters (blue circles).

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